高温后岩石变形破坏过程的能量分析  

Energy Analysis of Rock Deformation and Failure Process After High Temperature

作　　者：徐小丽[1] 高峰[2] 周清[1] 陈静[1] 

机构地区：[1]南通大学建筑工程学院,南通226019 [2]中国矿业大学深部岩土力学与地下工程国家重点实验室,徐州221008

出　　处：《武汉理工大学学报》2011年第1期104-107,124,共5页Journal of Wuhan University of Technology

基　　金：国家重点基础研究发展规划项目"973"(2010CB226804);江苏省高校自然科学研究项目(09KJB130001);南通大学引进人才科研项目(09R10)

摘　　要：从非平衡热力学角度出发,结合岩石在不同高温作用后的单轴压缩和声发射试验,详细阐述了岩石变形破坏过程中的声发射特点,分析了经历不同高温后岩石强度与能量耗散和能量释放之间的关系。研究结果表明高温作用后花岗岩声发射曲线大致经历了以下6个阶段:初始沉寂段、上升段、前峰值段、高幅持续段、后峰值段、后期沉寂段。声发射曲线较好地反映了岩石在整个破坏过程中由稳定态向亚稳定态、临界态、失稳破坏直至新的稳定态的发展过程。岩石峰值强度与耗散能呈反比关系,与弹性能呈正比关系,能量耗散使材料发生劣化,强度降低。声发射能率与弹性能呈正比关系,与耗散能呈反比关系,弹性能突然释放引起岩石的失稳破坏。岩石的破坏是能量耗散与能量释放共同作用的结果。研究结果有助于研究高温后受外载岩石微缺陷的演化并最终破裂的过程,对高温后岩体工程起到一定的参考作用。Mechanical characteristics and acoustic emission properties of granite under uniaxial compression after high temperature have been researched.Based on the experiments,the paper interprets the acoustic emission and energy characteristics of rocks in deformation and fracture process with non-equilibrium thermodynamic theory.The intrinsic relations between strength,energy dissipation and energy release of rocks during failure process are also discussed.The results show that after high temperature acoustic emission curves experienced six stages which contain initial dreariness stage,upword stage,anterior peak value stage,high-amplitude continuous stage,posterior peak value stage and later dreariness stage.Acoustic emission curves can preferably reflect rock developing process from stable state to metastable state,critical state,unstable failure until new stable state in deformation and fracture process.Rock strength shows inverse ratio to dissipated energy and proportional ratio to elastic energy,energy dissipation makes the material deteriorate and its strength drop down eventually.Acoustic emission energy rate shows proportional ratio to elastic energy and inverse ratio to dissipated energy,the elastic energy released in rock volume plays the pivotal role of abrupt structural failure of rock.It is emphasized that the failure of rock is a process in which energy dissipation and energy release occur simultaneously.The results contribute to study rock failure process from the micro defect evolution to finally rupture after high temperature from the viewpoint of energy,which offer reference to the engineering practice.

关 键 词：岩石 温度 声发射 耗散能 弹性能 

分 类 号：TU452[建筑科学—岩土工程]